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95% Efficiency & Combi Available!

K2 Firetube

Condensing Gas Boiler
Stainless Steel Heat Exchanger

The NEW K2 Firetube condensing boiler is an addition to the K2 high-efficiency series. Joining the K2 Watertube boiler, the K2 Firetube features a stainless steel vertical firetube heat exchanger and is available in six sizes. All models can be wall-hung and feature 5:1 modulation. The boiler’s dimpled, firetube heat exchanger provides lower pressure drop when compared to water-tube heat exchangers of similar capacity.

  • 95% AFUE – high efficiency and low emissions!
  • Six wall hung models; 85, 110, 155, 205, 270 MBH (combi version available for 155 MBH)
  • Field proven, stainless steel fire tube heat heat exchanger
  • Advanced Sage2.2 Boiler Control provides “out-of-the-box” high performance and easy setup
  • FULL SIZE easy access side service panel
  • UNMATCHED High Altitude Performance
  • Versatile top and bottom connections for supply & return (on heating-only boilers)
  • Universal vent connection for CPVC/PVC, polypropylene
  • ENERGY STAR Certified – Efficiency tax credits/rebates may apply
  • 5-year parts warranty

 

Accessories for the K2 Firetube boiler include:

usboilersagezonecontrol

 

 

Sage Zone Control – Precisely calculates heating demand from different zones and “re-sizes” the K2 boiler for optimum efficiency and whole home comfort.

  • Technical Manuals & Information
  • ENERGY STAR Rated ENERGY STAR Rated
  • Sage2.2 Boiler Control System Sage2.2 Boiler Control System
  • Sage Zone Control Circulator & Valve Panels Sage Zone Control Circulator & Valve Panels
  • Related Water Heater Related Water Heater
  • Manufacturer's Warranty Manufacturer's Warranty
  • AHRI Energy Labels & Product Certification AHRI Energy Labels & Product Certification
U.S. Boiler Company is a leading manufacturer of home heating equipment, water boilers, steam boilers, hot water heaters, radiators and boiler control systems.
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